Infants and other incontinent individuals wear absorbent articles such as diapers to receive and contain urine and other body exudates. Absorbent articles function both to contain the discharged materials and to isolate the materials from the body of the wearer and from the wearer's garments and bed clothing. Disposable absorbent articles having many different designs are known in the art. For example, Re. U.S. Pat. No. 26,152 entitled "Disposable Diaper" issued to Duncan and Baker on Jan. 31, 1967, describes a disposable diaper which has achieved wide acceptance and commercial success. U.S. Pat. No. 3,860,003, entitled "Contractible Side Portions For Disposable Diaper", issued to Buell on Jan. 14, 1975, describes an improved disposable diaper having a elasticized leg cuff that has also achieved wide acceptance and commercial success.
However, absorbent articles have a tendency to sag or gap away from and to slip down the body of the wearer during use. This sagging, gapping and slipping is caused by the wearer as the wearer moves, breathes and changes positions, by the downward forces generated when the absorbent article is loaded with body exudates, and by the deformation of the materials of the absorbent article when subjected to such forces. This sagging, gapping and slipping of the absorbent article can lead to premature leakage and poor fit of the absorbent article especially in the waist and the leg regions.
In order to more snugly fit absorbent articles about the waist of the wearer, certain commercially available absorbent articles have been provided with elasticized waistbands and improved fastening systems. Examples of such disposable diapers are disclosed in U.S. Pat. No. 4,515,595 issued to Kievet and Osterhage on May 7, 1985, U.S. Pat. No. 5,151,092 issued to Buell et al. on Sep. 29, 1992, and U.S. Pat. No. 5,242,436 issued to Weil et al. on Sep. 7, 1993.
Typical elasticized waistbands comprise a precontracted waist feature having an elastic member affixed between the topsheet and the backsheet. The elasticized waistbands are, thus, designed such that the contraction provided by the manufacturer in the waist feature maintains a snug fit about the waist of the wearer during use (i.e. provide sustained dynamic fit). However, precontracted waist features generally add to the cost of the absorbent article due to costly and complex equipment required in the manufacturing process. Further, the fastening systems used in conjunction with precontracted waistbands typically comprise adhesive or mechanical fasteners that join the front and rear of the absorbent article in fastening zones located just below the precontracted waistband (or toward the core of the absorbent article). The waistbands and fastening systems are generally configured in this way to ensure that the fastening system does not interfere with the waistband's ability to provide dynamic fit about the waist of the wearer.
It has been found, though, that absorbent articles having precontracted waistbands and fastening systems as described above still have a tendency to sag, gap or slip during use and the precontracted waistbands have a tendency to rollover or roll-in at the front of the diaper resulting in a lack of fit about the waist of the wearer. Although two-point fastening systems have been developed in order to help prevent some of the sagging, gapping and waistband rollover associated with diapers having fastening systems as described above, the two-point fastening systems tend to be relatively expensive to manufacture. As described in U.S. Pat. No. 5,242,436 issued to Weil et al. on Sep. 7, 1993, the two-point fastening systems generally comprise at least one primary fastening means for providing closure of the diaper about the wearer and a secondary fastening means to provide tension throughout the waistband.
Thus, it would be advantageous to provide an absorbent article having an improved elastically extensible waistband and fastening system that provides better fit, wearer comfort and reduced leakage. It would also be advantageous to provide an absorbent article which has reduced sagging, gapping, rollover, or roll-in at the waist of the diaper as well as reduced overall slipping during use. Further, it would be advantageous to provide the benefits of the currently available waistbands without the costs associated with the complex process of manufacturing precontracted waistbands and the costs associated with two-point fastening systems.
Therefore, it is an object of the present invention to provide an absorbent article having sustained dynamic fit during use.
It is a further object of the present invention to provide an absorbent article that has an elastically extensible waistband and an improved fastening system that is aligned with the elastically extensible waistband to provide sustained dynamic fit and resistance to leakage.
It is still a further object of the present invention to provide an absorbent article that has a fastening system integrated with the waistband to reduce the likelihood of sagging, gapping or rollover in the waist region, and thus, reducing the need for a secondary fastening.
It is yet a further object of the present invention to provide an absorbent article with an elastically extensible, form fitting waistband without the costs or complexities involved with manufacture of the typical precontracted waistbands available to the consumer today.
These and other objects of the present invention will be more readily apparent when considered in reference to the following description and when taken in conjunction with the accompanying drawings.